The present invention relates generally to a spin module system, and more particularly, to a method and apparatus for preventing the deposition and accumulation of organic compounds on a substrate surface after forming a coating.
In manufacturing integrated circuits, a lithography process is used for reproducing layers to form structures on a semiconductor substrate. As a first step in a lithography process, a photoresist layer is coated onto a semiconductor substrate such that an image can be projected and developed thereon. The photoresist material is a liquid that is coated in a very thin layer on top of the substrate. In a conventional process for applying a photoresist coating material to a substrate, a spin dispenser module is normally used. The liquid coating material is dispensed over the substrate and the substrate spun so that a uniform coating remains on the substrate. One or more materials may be so dispensed and coat the substrate. The backside of the substrate is rinsed and the coating material removed from an edge of the substrate. The coating is allowed to dry before it is soft-baked to solidify.
An image pattern is then projected onto the photoresist material. In the developing process, a spin dispenser module is also used. The developer solution dissolves or chemically changes either the exposed portion or unexposed portion of the photoresist material. The developer solution is dispensed over the substrate in a scan pattern while the substrate spins. Once the chemical reaction takes place, the substrate is rinsed to remove a portion of the photoresist material. The resulting coat pattern is baked to harden and may be used as a mask for an etch step or a deposition step to form a subsequent layer on the substrate. As the feature sizes decrease for integrated circuits, the quality of the coating and developing becomes more important. Defects may form by deposition of unwanted material during and after the coating and developing processes. Therefore, improved method and apparatus continues to be sought.